package com.sky.service.impl;

import com.alibaba.fastjson.JSON;
import com.sky.constant.MessageConstant;
import com.sky.dto.UserLoginDTO;
import com.sky.entity.User;
import com.sky.exception.LoginFailedException;
import com.sky.mapper.UserMapper;
import com.sky.properties.WeChatProperties;
import com.sky.service.UserService;
import com.sky.utils.HttpClientUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.io.IOException;
import java.time.LocalDateTime;
import java.util.HashMap;
import java.util.Map;


@Service
public class UserServiceImpl implements UserService {

    @Autowired
    UserMapper userMapper;

    private static final String wx_LoginUrl = "https://api.weixin.qq.com/sns/jscode2session";

    @Autowired
    WeChatProperties weChatProperties;

    @Override
    public User login(UserLoginDTO loginDTO) {

//        向wx API发送请求，获取openid
        try {
            String openId = getOpenId(loginDTO.getCode());
            // openid为空，抛异常
            if (openId == null){
                throw new LoginFailedException(MessageConstant.LOGIN_FAILED);
            }
            //        根据openid查询数据库，获取用户信息
            User user = userMapper.getByOpenId(openId);

//        如果是新用户，注册
            if (user == null){
                user = User.builder()
                        .openid(openId)
                        .createTime(LocalDateTime.now())
                        .build();
                userMapper.insert(user);
            }

//        返回用户信息
            return user;

        }catch (IOException e){
            e.printStackTrace();
        }
        return null;
    }

    private String getOpenId(String code) throws IOException {

        Map<String,String> map = new HashMap<>();
        map.put("appid",weChatProperties.getAppid());
        map.put("secret",weChatProperties.getSecret());
        map.put("js_code",code);
        map.put("grant_type","authorization_code");
        String response = HttpClientUtil.doPost(wx_LoginUrl, map);  // json String

        return JSON.parseObject(response).getString("openid");

    }
}
